Olympic fencing is so fast that the human eye can't score it anymore. This highlights how fast that is---and how the systems, with electronic "touch" sensors which trigger on the electrical circuit being closed on contact (knew that) and at certain force levels (didn't know that) register the hits/"touches".
Also: Very Cool Translation---"More Enjoy Fencing"
I was interested to see that "point scoring" blows are, of course, not really "combat blows"...
Wapping someone on the back? Would that stop them? Wouldn't it just tick them off? (1:22).
On the other hand, something directly into your heart (1:03)---that might check even a determined opponent with a real weapon. Drop him right there before hit strikes back once? Maybe not. Kill him within a minute or two--by causing pump failure (cardiac tamponade), dropping a lung (pneumothorax) or funny heart electrical donation problems (arrhythmia)---yah, I could see that.